change test class name

```
[info] [info] Compiling 2 Scala sources to /private/var/folders/gx/r4knnkks71v8dgx96xsspr440000gn/T/sbt_bb59d7e/gen/target/scala-2.11/test-classes...
[info] [error] /private/var/folders/gx/r4knnkks71v8dgx96xsspr440000gn/T/sbt_bb59d7e/gen/src/test/scala/app/models/ProgrammersSpec.scala:9: overriding method p in trait FormattingFragments of type => org.specs2.specification.Fragments;
[info] [error]  value p needs `override' modifier
[info] [error]   val p = Programmers.syntax("p")
[info] [error]       ^
[info] [error] one error found
[info] [error] (test:compile) Compilation failed
[info] [error] Total time: 3 s, completed May 11, 2014 12:05:13 PM
[error] x scalikejdbc-mapper-generator / gen
[error]    {line 34}  Command failed: + failed
java.lang.RuntimeException: Failed tests:
  scalikejdbc-mapper-generator / gen

  at scala.sys.package$.error(package.scala:27)
  at sbt.test.ScriptedTests$.runAll(ScriptedTests.scala:128)
  at sbt.test.ScriptedTests$.run(ScriptedTests.scala:122)
  at sbt.test.ScriptedTests$.run(ScriptedTests.scala:114)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:606)
  at sbt.ScriptedPlugin$$anonfun$scriptedTask$1$$anonfun$apply$1$$anonfun$apply$2.apply(ScriptedPlugin.scala:44)
  at sbt.ScriptedPlugin$$anonfun$scriptedTask$1$$anonfun$apply$1$$anonfun$apply$2.apply(ScriptedPlugin.scala:40)
  at scala.Function1$$anonfun$compose$1.apply(Function1.scala:47)
  at sbt.$tilde$greater$$anonfun$$u2219$1.apply(TypeFunctions.scala:42)
  at sbt.std.Transform$$anon$4.work(System.scala:64)
  at sbt.Execute$$anonfun$submit$1$$anonfun$apply$1.apply(Execute.scala:237)
  at sbt.Execute$$anonfun$submit$1$$anonfun$apply$1.apply(Execute.scala:237)
  at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:18)
  at sbt.Execute.work(Execute.scala:244)
  at sbt.Execute$$anonfun$submit$1.apply(Execute.scala:237)
  at sbt.Execute$$anonfun$submit$1.apply(Execute.scala:237)
  at sbt.ConcurrentRestrictions$$anon$4$$anonfun$1.apply(ConcurrentRestrictions.scala:160)
  at sbt.CompletionService$$anon$2.call(CompletionService.scala:30)
  at java.util.concurrent.FutureTask.run(FutureTask.java:262)
  at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
  at java.util.concurrent.FutureTask.run(FutureTask.java:262)
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
  at java.lang.Thread.run(Thread.java:744)
[error] (mapper-generator/*:scripted) Failed tests:
[error]   scalikejdbc-mapper-generator / gen
```
avoid method name conflict

specs2 mutable specification has "p" and "t" method
https://github.com/etorreborre/specs2/blob/SPECS2-2.3.11/core/src/main/scala/org/specs2/specification/FormattingFragments.scala#L8
https://github.com/etorreborre/specs2/blob/SPECS2-2.3.11/core/src/main/scala/org/specs2/specification/FormattingFragments.scala#L11

see 06fa69cd265edb5506e780c7ab20492d45c73b3b
Merge pull request #249 from xuwei-k/specs2-mutable-specification-has-p-method

avoid method name conflict